Cobute Slab System

The Cobute precast slabs are structurally more efficient and considerably lighter than solid slabs or even conventional rib and block slabs
— Pr.Eng. Ugo Rivera

Unlike conventional rib and block slabs, the Cobute precast slab is an interlocking and modular system with three elements: precast lattice ribs, precast panels and polystyrene blocks. With a deadload of roughly 97 kg/m², the Cobute decking is lightest slab on the market. The principal steel reinforcement is added during the manufacturing stage, with additional steel added on site. The R Value of the Cobute slab ranges according to the height of the slab - in addition, the slab holds a Fire Certificate rating of 150 minutes for a 230 mm thick slab.

When the Cobute precast systems are used in combination, the project can be cast in one pour, minimising risks of cold joints that leads to cracking.

The elements of the Cobute precast slab system


Technical details


The lattice rib comes in standard width and thickness. The rib stirrup height changes according to the slab thickness, as specified by the Engineer. The stirrups are produced with high tensile steel in a continuous bent-length, providing a superior sheer-key between the precast rib and the cast in-situ topping. Precast ribs with stepped top steel are available, as well as edge ribs, depending on individual requirements.


Cobute precast slab - polystyrene detail


Precast panels for the slab

The precast panels are manufactured in a standard size, light and easy to install; panels complement the structure of the rib as they interlock with precision. Cobute can accommodate special requests such as creating perforated panels for light points, down lighters or speaker boxes as well as supplying narrower panels to minimise shuttering on site.


The use of polystyrene has void formers offers incredible advantages such as:

  • thermal and acoustic insulation

  • concrete savings

  • lightweight of slab and structure

  • variation in slab thicknesses


Typical Section of Cobute slab

Cobute manufactures R.C. precast slabs in thicknesses varying from 150 to 350 mm, in increments of 25 mm for intermediate thickness. When designing different slab heights,  only the height of the lattice rib and the thickness and length of the polystyrene blocks will changewithout increasing the total amount of concrete needed.


What sets the Cobute slab apart?

Cobute precast beam, decking and stair integration

  • It's the lightest slab (the dead load of the decking system is roughly 97 kg/m²)

  • It's a flexible system that suits a wide range of structures and thicknesses

  • It guarantees thermal insulation

  • It holds a fire rating certificate

  • It reduces the amount of resource needed

  • Only minimal shuttering is required.

Cobute decking.PNG

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